information psychophysics

The application of visual psychophysical techniques to perception of information conveyed through a visual representation.

information scent

The relation of environmental cues in the environment (such as bibliographic citations, or World Wide Web link text) to users’ assessments of the value of information sources.

information visualizations

The use of computer-supported, interactive, visual representations of abstract data to amplify cognition.

interaction language

The commands used to instruct an interactive information artifact such as a word processor or a heating controller. These commands are a form of notation, but typically what the user can see as feedback is the effect of the command rather than the command itself. For example, in a word processor’s interaction language, giving the command Delete Word deletes a word; in the same word processor’s macro language, however, giving the same command Delete Word inserts the appropriate symbols into a program. See also notation.

joint action

Both people involved in a joint action intend to do their part and believe that the joint action includes their and the other person’s part. (See the text for a more formal and comprehensive definition.)

juxtaposability

A level of visibility (in the cognitive-dimensions framework) at which any required subset of components can be viewed simultaneously. It is an essential requirement for certain cognitive strategies, such as design by modification of existing material, or for checking consistency of form across instances of similar components. See also visibility.

K

A standard operator in a keystroke-level model (KLM), K represents the act of striking a key on an input device like a keyboard or a mouse. The duration depends on the device and the skill of the user. A variety of quantitative estimates can be found in Card, Moran, and Newell (1980b, 1983).

keystroke-level model (KLM)

The simplest GOMS technique. It provides standard keystroke-level operators (D, H, K, M, P, and R) with estimates of duration and rules for placing the M (mental) operators. It abstracts away from the goal hierarchy, multiple methods, and selection rules found in other GOMS techniques. More information can be found in Card, Moran, and Newell (1980b, 1983).

KLM

See keystroke-level model.

latent semantic analysis (LSA)

A statistical theory and method of identifying word meaning through analysis of context of word use.